Instant messaging software has become an indispensable communication tool in people's daily life. To protect the security of an instant messaging account, a user name and a password are required to match each other as an input during a login in order to pass a login verification. However, accounts are subjected to being hijacked and be disguised as a legitimate user in order to successfully login during identity verification. Further identity verification may be necessary to prevent the above-mentioned problem.
A short message verification code system may be used to perform further identity verification. In a short message verification code system, upon receiving a verification request from a terminal, a server may send a short message verification code to the terminal to be input by a user. If the short message verification code is correct, the identity verification may be successful.
Such identity verification still has at least the following problems: when a short message verification code system is used, if the mobile phone (i.e., terminal) which receives the short message verification code may not be available, identity verification may not be performed. Consequently, a short message verification code system may be applicable to very limited scenarios only, therefore may be too inflexible in other scenarios.